2-氟中氮茚衍生物的合成及表征

2-氟中氮茚衍生物的合成及表征;偶极反应;二氟乙烯基对甲苯磺酸酯;氟中氮茚;反应机理     

中氮茚腈类化合物的合成及其荧光性质的研究

合成了一系列中氮茚化合物,研究了化合物3a～3k,4a～4b,5～6分子中不同取代基对其荧光光谱和荧光量子效率的影响.发现中氮茚环上的氰基具有较好的荧光助色作用,中氮茚环上的COPh,COMe或CHO对分子的荧光具有猝灭作用;发现中氮茚类有机化合物的分子结构与荧光性质之间的某些关系.化合物3a～3b,3g～3i具有较高的荧光量子效率,可以作为比较好的有机荧光分子用于探针化合物的结构修饰.     

中氮茚的合成研究进展

中氮茚及其衍生物的特殊结构使得它们在生物、医药等领域具有广泛的应用. 其合成方法很多, 最近大量文献报道了它们的合成. 综述了近几年来中氮茚及其衍生物的合成方法, 并展望了其今后合成发展的方向.     

中氮茚萘醌类化合物与小牛胸腺dna的相互作用

中氮茚萘醌;小牛胸腺dna;电化学;uv-vis吸收光谱     

铱催化中氮茚衍生物的Friedel-Crafts类型不对称烯丙基取代反应

本工作报道了金属铱催化烯丙醇与中氮茚衍生物Friedel-Crafts类型的不对称烯丙基取代反应.该方法在温和条件下,以优秀的收率以及对映选择性控制合成了一系列C3位烯丙基化的中氮茚衍生物,为构建手性中氮茚化合物提供了一条新策略.     

4-甲基吡咯并[2,1,5-cd]中氮茚的合成

以2-乙基吡啶生成的叶立德为原料,采用1,3-偶极环加成反应,得到了一系列3-乙酰基(或苯甲酰基)-5-乙基中氮茚衍生物,后者与KOH在加热条件下发生分子内缩合,得到了一系列4-甲基吡咯并[2,1,5-cd]中氮茚.     

氨基苯基类中氮茚化合物的合成及作为质子探针的研究

设计合成了3个氨基苯基类中氮茚化合物, 研究了其在不同pH值的缓冲溶液中的荧光强度变化. 结果表明, 在pH=2.1～4.2之间, 该类化合物具有荧光敏感性. 化合物3a和3b可以作为良好的质子控制的荧光开关器件信号分子.     

含中氮茚基团的偶氮染料的合成及其吸收光谱

通过简单的方法合成了4个新的中氮茚偶氮类化合物,并通过元素分析、红外光谱及核磁共振谱表征了其结构。测定了它们的热稳定性,研究了它们在不同溶剂中以及不同pH条件下的紫外光谱性质。我们发现当化合物中的羧基以羧酸负离子存在时最大吸收波长蓝移。     

以缺电子炔烃为原料经1,3-偶极环加成反应合成3-芳基中氮茚的新方法

报道了一种简便有效地合成3-芳基中氮茚的方法.反应需要的吡啶鎓盐可以用吡啶和苄卤很容易制得,然后以1,4-二氧六环为溶剂,在碳酸铯存在的条件下与缺电子炔烃经1,3-偶极环加成和芳构化反应即可得到3-芳基中氮茚,产率34%~81%.该方法具有原料易得、操作简便、反应条件温和、选择性好等优点.     

新型水溶性中氮茚衍生物的合成及铜离子荧光探针行为

设计合成了2个新型水溶性中氮茚季铵盐化合物4a{氯化2-[N'-(3-氰基-中氮茚-1-甲酰基)肼基]酰乙基-1-吡啶鎓盐}和4b{氯化2-[N'-(3-氰基-中氮茚-1-甲酰基)肼基]酰乙基-1-(2-甲基吡啶)鎓盐},采用红外光谱、核磁共振、质谱和元素分析对其进行了结构表征,并研究了它们的光谱性质.选取Cu2+,Zn2+,Ca2+,Cr3+,Co2+,Al3+,Mn2+,Ni2+,Ba2+,Hg2+,Fe3+,Cd2+,Mg2+,Pb2+,Li+和Ag+等16种常见金属离子,对2个化合物进行了离子识别实验.结果表明,化合物4a和4b在一定浓度范围内对铜离子均具有良好的选择性识别能力,受常见离子干扰小.由于空间位阻的影响,化合物4a具有比4b更高的灵敏性.     

A supercooled imidazolium iodide ionic liquid as a low-viscosity electrolyte for dye-sensitized solar cells

A series of allyl-functionalized imidazolium salts are reported, including 1-allyl-3-ethylimidazolium iodide and 1-allyl-3-propylimidazolium iodide, which have melting points close to room temperature and show typical properties of supercooled fluids if heated above their melting points. Their viscosities in the liquid state are considerably lower than the benchmark ionic liquid used in solar cells, viz., 1-propyl-3-methylimidazolium iodide. Electrolytes containing these new liquids provide excellent efficiencies and good stability in dye-sensitized solar cells when subjected to an accelerated-light soaking test at 60 degrees C. The structures of three of the new salts have been established in the solid state by single-crystal X-ray analysis.     

Ce^3＋—Gd^3＋在某些稀土硼酸盐体系中的能量传递

Ce~(3 )离子有一个宽而强的4f-5d吸收带,它能有效地吸收能量。Ce~(3 )离子的荧光寿命非常短,能将能量有效地传递给其它离子起敏化作用。对于Ce~(3 )→Tb~3 ),Ce~(3 )→EU~(3 )和Ce~(2 )→Mn~(3 )的敏化作用已有许多报导,并在灯用发光材料上获得应用。Blasse等提出在Ce~(3 )敏化Tb~(3 )时。用Gd~(3 )作中间体能获得高效发光材料。由于Ce~(3 )的5d能级强烈地依赖于基质,其发射波长可以从紫外到红区,而Gd~(3 )的4f-4f跃迁的激发和发射峰值随基质的变化改变不大,因此将有可能呈现不同的Ce~(3 )-Gd~(3 )的能量转移过程。     

Electronic and steric factors in reactions involving the formation of spiropyrans

A study of the properties of six-membered heterocyclic cations with a methyl group in the position makes it possible to reveal the relative roles played by electronic and steric factors for the conversion of the corresponding o-oxidostyryl derivatives to spiropyrans. The positive charge on the carbon atom in the investigated bicyclic heterocations increases in the order 1,2-dimethylisoquinolinium <1,2-dimethylquinolinium <1,2,3-trimethylquinolinium <1,2-dimethyl-3,4-dihydroisoquinolinium, whereas the rates of reaction with p-dimethylaminobenzaldehyde follow a different sequence — 1,2-dimethylisoquinolinium <1,2,3-trimethylquinolinium <1,2-dimethyl-3,4-dihydroisoquinolinium <1,2-dimethylquinolinium. The ability of o-oxidostyryl isoquinolinium and 1,3-dimethylquinolinium derivatives to form spiropyrans, in contrast to 1-methylquinolinium derivatives, is due to the steric effect of the hydrogen atom in the peri position or of the methyl group near the reaction center, which leads to disruption of the coplanarity and a decrease in the stabilities of the corresponding merocyanine molecules.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 818–827, June, 1976.     

(Perhalogenmethylthio)heterocyclen. XVIII . Synthese und eigenschaften von halogenierten (perhalogenmethylthio)pyrrolen

(Trifluoromethyltho)pyrroles 1-5 and (chlorodifluoromethylthio)pyrroles 6 were chlorinated by sulfuryl chloride, sulfuryl chloride/silicon dioxide, sulfuryl chloride/disulfur dichloried/aluminium trichloried to give the corresponding chloropyrroles 1a-d , 2a,b , 3a,b , 4a , 5a , and 6a-c Bromination with bromine or iodination with iodine/potassium iodide of 2, 3, 4 , and 6 yielded the derivatives 2c,d, 3c,d, 4b, 6d , and 2e, 3e, f, 4c , 6e respectively. Mixed halogenated pyrroles 3g and h were obtained from 3a and bromne or 3a and iodine/potassium iodide. During some chlorination reactions 7, 8 , and 9 were fromed in low yield asbyproducts. The ¹H-nmr, ¹⁹F-nmr and ir spectroscopic data are presented.     

Molecular assemblies from imidazolyl-containing haloalkenes and haloalkynes: competition between halogen and hydrogen bonding

The structural characterization of molecular assemblies constructed from imidazolyl-containing haloalkenes and haloalkynes is reported. 1-(3-Iodopropargyl)imidazole (2) and 1-(2,3,3-triiodoallyl)imidazole (5) were synthesized from 1-propargylimidazole (1). In the solid state, these wholly organic modules self-assemble through N...I halogen-bonding interactions, thus giving rise to polymeric chains. The N...I interaction observed in 2 (d(N...I)=2.717 A, angle-spherical C(sp)-I...N=175.8 degrees) is quite strong relative to previously reported data. The N...I interaction in 5 (d(N...I)=2.901 A, angle-spherical C(sp2)-I...N=173.6 degrees) is weaker, in accordance with the order C(sp)-X<--base>C(sp2)-X<--base. Compound 5 was found to give a 1:1 cocrystal 4 with morpholinium iodide (6). In the X-ray crystal studies of 4, N...I halogen-bonding interactions similar to those observed in 5 were shown not to be present, as the arrangement of the molecules is governed by two interwoven hydrogen-bonding networks. The first network involves N-H...O interactions between nearby morpholinium cations, and the second network is based on N-H...N hydrogen bonding between morpholinium cations and imidazolyl groups. Both hydrogen-bonding schemes are charge-assisted. Halogen bonding is not completely wiped out, however, as the triiodoalkene fragment forms a halogen bond with an iodide anion in its vicinity (d(I...I)=3.470 A, angle-spherical C(sp2)-I...I=170.7 degrees). X-ray crystal studies of 6 show a completely different arrangement from that observed in 4, namely, N-H...O interactions are not present. In crystalline 6, morpholinium cations are interconnected through C-H...O bridges (d(H...O)=2.521 and 2.676 A), and the NH2+ groups interact with nearby iodide anions (d(H...I)=2.633 and 2.698 A).     

Mesoionic dimethyl derivatives of some 1,2,4-triazinones. The course of the reaction of 3,5-dimethoxy, 3-methoxy-5-methylthio, 5-methoxy-3- methylthio and 3,5-bis(methylthio)-1,2,4-triazine with methyl iodide

Treatment of 3,5-dimethoxy-1,2,4-triazine ( 1a ) with methyl iodide was found to give depending on the reaction time triazinium iodide 2a , triaziniumolates 4a and 6a as well as methoxytriazinones 7a and 8a . Thermolysis of 2a gave triaziniumolates 4a and 6a . Reaction of 2a , 4a or methoxytriazinone 9a with methyl iodide in acetonitrile yielded as the sole product 6a . Reaction of 3-methoxy-5-methylthio-1,2,4-tri-azine (1b ) with methyl iodide gave triazinium iodide 2b and methylthio triazinone 7b . Hydrolysis of 2a,b afforded 4a . Reaction of 5-methoxy-3-methylthio-1,2,4-triazine ( 1c ) with methyl iodide gave triazinium iodide 2c , triaziniumolate 4b , triazinium iodide 5b and triazinone 8b . Hydrolysis of 2c yielded 4b and its thermolysis gave a mixture of 4b and 5b . Reaction of 2c , 4b and triazinone 9b with methyl iodide afforded 5b . Treatment of 3,5-bis(methylthio)-1,2,4-triazine ( 1d ) with methyl iodide was found to give a mixture of N1 and N2 methiodides 2d and 3d which gave on hydrolysis 4b and 8b , respectively. Methylation of 6-methyl derivatives 1c-g gave analogous results, however the proportions of N1 methylated products were lower and the reaction rates higher in comparison to their respective lower homologues 1a,c,d . The structures of the mesoionic dimethyl derivatives were assigned from uv, ir, ¹H nmr and electron impact mass spectra. The structural assignments were eventually confirmed by quantum chemical calculations of net charge distributions, bond lengths and ipso angles of the C5?O bonds.     

Synthesis and surface properties of new semi-fluorinated sulfobetaines potentially usable for 2D-electrophoresis

New semi-fluorinated amidosulfobetaines, homologs of hydrocarbon amidosulfobetaines (ASB) commonly used in two-dimensional gel electrophoresis (2DE), were prepared in three steps from 2-F-alkylethyl iodide or F-alkyl iodide. Their synthesis was described and their air-water interface properties were investigated and compared with their perhydrogenated counterpart properties. The influence of the relative lengths of the perfluorinated and hydocarbonated moieties was discussed. 2DE of a rat testicular membrane fraction was performed comparatively using one of these fluorinated sulfobetaines and its hydrocarbon homolog; these preliminary results showed the great potential of the semi-fluorinated sulfobetaines in proteomic analysis.     

A divergent synthesis of dihydropyridazinones,N‐substituted dihydropyrazoles,and O‐substituted pyrazoles

Dihydropyridazinones 4a , 4b , N‐substituted dihydropyrazoles 5b , 5c , 5d , and O‐substituted pyrazoles 6a , 6b , 6c , 6d have been synthesized starting from spirocyclopropanepyrazole derivative 2 . Treatment of 2 with α‐chloro esters, e.g., methyl chloroacetate, ethyl chloroacetate, isopropyl chloroacetate, and tert‐butyl chloroacetate, in potassium carbonate/sodium iodide system caused ring opening and subsequent C‐ or N‐attack nucleophilic substitution to give the corresponding dihydropyridazinones 4a , 4b and N‐substituted dihydropyrazoles 5b , 5c , 5d . On the other hand, in the absence of sodium iodide, O‐substituted pyrazoles 6a , 6b , 6c , 6d were obtained from 2 via an O‐attack nucleophilic substitution. J. Heterocyclic Chem., 2011.     

卤化银乳剂微晶体的结构与性能研究 Ⅴ.八面体核壳复合结构乳剂的电性质与感光性能

本工作应用双注法制备了一系列不同碘含量的八面体核壳孔剂。测定了它们的光吸收,离子电导(介电损耗法)、光电导(微波光导法)和感光性能。结果表明:乳剂微晶体的光吸收和离子电导随着碘含量的增加而显著上升,光电导也随着碘含量的增加而增大,其光电子表减过程遵循二级反应动力学过程,光电子半衰期在碘含量为5mol%时为最大。在相同的化学敏化条件下,乳剂的感光度随碘含量增加而上升(碘含量0-12.5mol%)。     

Synthesis and theoretical studies on rare three-coordinate lead complexes

A series of beta-diketiminate lead halide complexes has been synthesised LPbCl (2), LPbBr (3) and LPbI (4) (L = {N(2,6-(i)Pr(2)C(6)H(3))C(Me)}2CH]), which includes a rare example of a three-coordinate lead iodide (4). The chloride and bromide complexes, 2 and 3, are relatively stable in both the solid and solution states, only slowly decomposing to elemental lead over the course of a month in solution, the lead iodide 4 appears to be less stable and decomposes after 3 d in the solid state at ambient temperatures. The lead chloride complex 2 was treated with KN(SiMe3)2 to yield an unusual terminal lead amide complex LPbN(SiMe3)2 (5). Unlike three-coordinate beta-diketiminate transition metal-halide complexes, the ligands are present in a pyramidal arrangement around the lead centre, commonly attributed to the presence of a stereochemically active lone pair. We have investigated the influence of this lone pair on the geometry of the metal halide complexes 2-4, as well as the isostructural germanium and tin complexes (6 and 7, respectively) using DFT calculations. The lone pair in the lead complexes is significantly more diffuse than in the tin and germanium analogues and only a small amount of hybridisation between the 6s and 6p orbitals is observed.